The sampling system design for welding process based on STM32 micro-controller

To analyze welding quality and optimize welding procedure, sampling system for welding process based on STM32 Micro-controller is proposed. The system acquires welding current and voltage in high accuracy and sample rate, then transmits data to upper computer via Modbus RTU protocol on RS-485. Due to special protective circuit design, this system can be applied in a variety of welding methods such as gas metal arc welding (GMAW), gas tungsten arc welding (GTAW), shielded metal arc welding (SMAW), submerged arc welding (SAW), etc. the hardware works stably with high reliability. Human-machine interface is designed by C# programming language. It has powerful function including waveform real-time display, welding quality analysis, historical information query, etc. The system structure is introduced in this paper. Circuit design and principle are described in detail. This system has been realized and used in one factory of Dongfang Boiler Group co., LTD.